LIVER RESPONSE TO THE CONSUMPTION OF FRIED SUNFLOWER OIL.

Sunflower oil is one of the most commonly used fat sources in Argentina, and deep-fat frying is the popular food preparation process. The liver response of feeding a diet containing fried sunflower oil (SFOx) on growing rats was studied. Thirty-nine male weanling Wistar rats were randomly assigned to one of three diets for 8 wks: control (C), a sunflower oil (SFO) and a diet containing SFOx, both of the sunflower diets were mixed with a commercial rat chow at weight ratio of 13% (w/w). Body weight and food consumption were recorded weekly. At t=8 wk, lipid profile and glycemia were measured. Visceral adiposity was registered. Liver was weighed and preserved for histological analysis, relative fatty acid profile, fibrosis markers and oxidative status. The three diets did not alter body weights; however, the SFOx fed rats showed increased energy intake and visceral fat; therefore, in liver saturated fat content, trans fatty acids, plus other unidentified minor components, such as hydroperoxides, hydroxides, epidioxides, hydroperoxy epidioxides, hydroxylepidioxides, and epoxides, were detected. The hepatosomatic index of SFOx rats was altered and showed hepatic steatosis. SFOx rats exhibited increased liver dichlorodihydrofluorescein-diacetate and thiobarbituric acid substance levels and oxidized-proteins content. Their livers had lower relative levels of monounsaturated, polyunsaturated fatty acids and catalase activity, but matrix metalloproteinase-9 activity was unchanged. Consumption of a diet rich in fried oil during growth could induce liver damage due to steatosis, excessive lipid toxicity and the accumulation of reactive oxygen species. Further progression could lead to hepatic fibrosis.

Effect of fried sunflower oil intake on mandibular biomechanical competence of growing rats / Efecto del consumo de aceite de girasol termooxidado sobre la competencia biomecánica de la mandíbula, en animales en crecimiento

ABSTRACT Previous studies by us demonstrated that the consumption of thermally oxidized oil diet adversely affects body growth, lipid metabolism, bone mass and femur biomechanical competence. Aim: The aim of this study was to evaluate the effects of a diet containing fried sunflower oil on the mandible of growing rats. Materials and Method: Male Wistar rats (21±1 day old) (n=21) were assigned at weaning to one of three diets for 8 weeks: a control diet (C), a diet containing sunflower oil (SFO) or a diet containing sunflower oil that had been repeatedly heated (SFOx); both SFO and SFOx were mixed with commercial rat chow at 13% (w/w). The consistency and viscosity of the 3 diets were similar. Zoometrics and food intake were recorded weekly. At wk=8, mandibular growth was assessed by measurements of anatomical points of cleaned bones, and mandible biomechanical competence was assessed to estimate the structural properties of the bone. Statistical analysis was performed by SPSS v. 20.0. Results: Rats fed SFOx diet attained the lowest final body weight (P=0.0074), mandibular weight (P=0.0001) and mandibular /length (P=0.0002). Load bearing capacity (Wf;N), load of yielding (Wy;N) and stiffness (Wy/dy;N/mm) of the mandible were negatively affected by both sunflower oil diets (fresh and fried) (P=0.001; P=0.002; P=0.003, respectively) though SFOx induced the most significant reduction in Wy/dy (C:44.4(5.4) > SFO:36.1(2.1) > SFOx: 26.3(3.7) N/ mm; P=0.003). The deleterious effect of SFOx on mandibular growth was more accentuated on the posterior part of the bone (C:11.4(0.3)=SFO:11.2(0.2)>SFOx: 10.7(0.2) mm; p=0.0005); the anterior/ posterior ratio (C:1.25(0.02)=SFO:1.27(0.02)<SFOx:1.32(0.03); p=0.0001) indicated that SFOx induced mandibular deformation. Conclusion: Consumption of SFOx diet during growth could affect mandibular morphometric properties and biomechanical competence, in terms of bone stiffness.

RESUMEN En estudios previos hemos demostrado los efectos adversos del consumo de una dieta rica en aceite termooxidado sobre el crecimiento corporal, el metabolismo de los lípidos, la masa ósea y la competencia biomecánica del fémur. Objetivo: El objetivo de este trabajo fue investigar el efecto de una dieta rica en aceite de girasol termooxidado (AGX) sobre los parámetros morfométricos y biomecánicos de la mandíbula de rata en crecimiento. Materiales y Método: Ratas macho Wistar de 22±1 días de edad (n=21) recibieron durante 8 semanas una de 3 dietas: control (C); dieta comercial, una dieta suplementada con aceite de girasol (AG) y una dieta suplementada con AGX. La consistencia y la viscosidad de las dietas fueron similares. Los parámetros zoométricos y el consumo de dieta se registraron semanalmente. A T=8, los animales se eutanasiaron y se obtuvieron las hemimandíbulas. El crecimiento mandibular se estimó por medidas morfométricas entre puntos anatómicos y las propiedades estructurales por biomecánica. El análisis estadístico se realizó por SPSS v. 20.0. Resultados: Las ratas alimentadas con AGX presentaron menor peso corporal final (p=0.0074), peso mandibular (p=0.0001) y longitud mandibular (p=0.0002). Las propiedades estructurales de la mandíbula, Wf (p=0.001), Wy (p=0.002) y Wy/dy (p=0.003), se vieron afectadas negativamente en ratas alimentadas con AG o AGX, respecto a C; pero la rigidez ósea (Wy/dy) en AGX fue significativamente menor (C:44.4(5.4) > SFO:36.1(2.1) > SFOx: 26.3(3.7) N/mm; p=0.003). El efecto deletéreo del AGX sobre el crecimiento mandibular fue más acentuado en la región posterior (C:11.4(0.3)=SFO:11.2(0.2)>SFOx: 10.7(0.2) mm; p=0.0005). La relación anterior/posterior (C=1.25 (0.02); AG= 1.27(0.02) y AGX=1.32(0.03), p=0.001) indica que AGX indujo deformación mandibular. Conclusiones: El efecto adverso del consumo de una dieta rica en AGX durante el crecimiento podría afectar los parámetros morfométricos y la biomecánica ósea en términos de rigidez ósea.

Aceite de girasol alto oleico: hacia la construcción de una grasa saludable / High oleic sunflower oil supplemented: towards the construction of a healthful fat

Introducción: dado que el aceite de girasol alto oleico (AGAO) es una alternativa viable, ampliamente utilizada, planteamos el agregado de fitoesteroles o aceite de pescado como una nueva estrategia nutricional que logre posicionar al AGAO como una fuente de lípidos saludable. Objetivos: evaluar el efecto del enriquecimiento de AGAO con fitoesteroles (AGAO-F) naturales o suplementación con aceite de pescado (AGAO-n3) sobre el perfil lipídico-lipoproteico, la grasa corporal total y la masa ósea, en un modelo experimental de hipercolesterolemia nutricional (HCN) en crecimiento y analizar el beneficio de dicho enriquecimiento/suplementación en relación al aceite de oliva extra virgen (AO). Materiales y métodos: 48 ratas Wistar macho al destete recibieron por tres semanas (T3) una dieta aterogénica rica en grasa saturada (GS) y col para inducir HCN. A T3 se midió la colesterolemia (col-T) y se dividieron en cuatro grupos. Por cinco semanas (T8), se reemplazó GS por AGAO o AGAO-F o AGAO-n3 o AO. Las dietas se administraron ad libitum y se registró zoometría y consumo (kcal/100g peso corporal/día). A T8 se evaluaron: índice hepatosomático (IH, %), col-T, colnoHDL, col-HDL y TG séricos (mg/dL), % grasa corporal total y distribución, densidad (DMOg/cm2 ) y contenido mineral óseo (CMO,g) de esqueleto total (DPX). Resultados: sin diferencias en peso (g), longitud (cm), consumo e IH. AGAO-F mejoró todos los lípidos séricos. AGAO-n3 mostró menores niveles de col-T, col-noHDL (p=0,000); no de TG. Sin diferencias en grasa corporal y CMO; AGAO-n3: menor porcentaje de grasa intestinal (p=0,003) y DMO (p=0,03). Respecto a AO: AGAO-F y AGAO-n3 mejoraron el perfil-lipídico y AGAO-n3 < grasa intestinal. Conclusiones: en relación a AGAO y AO, AGAO-F y AGAOn3 disminuyeron el riesgo cardiometabólico. En relación a la masa ósea, el agregado de fitoesteroles o aceite de pescado no logró en el tiempo estudiado reducir el riesgo de osteopenia/ osteoporosis impuesto por la HCN.

Introduction: our previous studies demonstrated that the replacement of saturated fat by MUFA rich-diets ameliorated some of the alterations induced by saturated fat. Since high oleic sunflower oil (HOSO) constitutes an important source of MUFA and widely distributed in human nutrition, a supplementation of HOSO may prevent osteopenia and cardiovascular risk improving the biochemical profile. Objectives: the effects of replacing dietary saturated fat, by different ω-9MUFA sources supplemented with natural sterols or fish oil, on serum lipoprotein profile, body fat and distribution, bone mineral content and density in growing hypercholesterolemic rats, were studied. Materials and methods: forty eight Wistar rats (aged=21days) were fed "ad libitum" with an atherogenic diet, rich in saturated fat and cholesterol for 3 weeks, to induce hypercholesterolemia. Then, rats were randomly assigned to one of 4 groups, according to the source of oil replacing saturated fat: extra virgin olive oil (OO); HOSO, HOSO plus phytosterols (HOSO-P) or HOSO plus fish-oil (HOSO-F) for 5 weeks. After 3 weeks, zoometrics and diet consumption were recorded; hepatic index (HI), serum lipids, body fat content and distribution, bone mass content (BMC) and density (BMD), were assessed. Results: groups showed no significant differences in zoometrics, diet consumption and HI (p>0,05). HOSO-P rats showed a reduction in T-Chol and nonHDL-Chol and the lowest TG levels; HOSO-F showed lower T-chol and non HDL-chol levels (p=0,000), but not TG. Total body fat and BMC were not different among groups. HOSO-F rats showed the lowest intestinal fat content (p=0,003) and BMD (p=0,03). When compared to OO, HOSO-P and HOSO-F improved serum lipids and additionally, HOSO-F showed a reduction in intestinal fat. Conclusions: The replacement of saturated fat rich-diet by HOSO supplemented with phytosterols or fish oil induces bene- ficial effects on serum lipids and cardiovascular disease. However, they could not prevent the detrimental effects on bone.

Dietas ricas en grasa y composición corporal a lo largo de dos generaciones. Estudio experimental / High-fat diets and body composition over two generations. An experimental study

Antecedentes y objetivo A pesar de los últimos avances acerca de los factores nutricionales que inducen modificaciones epigenéticas, la información en edades tempranas es escasa. El presente trabajo estudió en un modelo experimental a lo largo de dos generaciones las posibles modificaciones en la composición corporal, la posible expresión de cambios epigenéticos, y el resultado del consumo de dietas isocalóricas con niveles de grasa diferentes. Materiales y métodos Ratas Wistar hembras al destete se dividieron en dos grupos que recibieron una dieta con 7 y 15% de grasa (rica en grasa). A los 70 días se aparearon (M1) y sus crías (C1) constituyeron la primera generación; C1 a los 70 días fueron apareadas (M2) y sus crías (C2) constituyeron la segunda generación. Al destete, se evaluaron tanto las madres como las crías (M1, M2 y C1, C2), el peso (P) y composición corporales % de grasa (% Gra), por método químico y contenido mineral óseo de esqueleto total (CMO) por densitometría, expresado como %CMO. Resultados Al destete, en los grupos con dieta rica en grasa M2 y C2 (15% Gra) se observó un incremento significativo del P y % Gra (p<0,05), mientras que el aumento en el % Gra ya se observó en C1 y M1 (p<0,001). Por el contrario, el % CMO de M2 y C2 disminuyó significativamente (p<0,001).Conclusión este estudio pone de manifiesto la potencial necesidad de modificar ciertos hábitos alimentarios que eviten repetir patrones distorsionados de generación en generación (AU)

Introduction and objective Despite recent findings reported on the nutritional factors that induce epigenetic changes, little information is available at early ages. This study analyzed in an experimental model, over two generations, potential changes in body composition and potential expression of epigenetic changes as the result of the intake of isoenergetic diets with different fat levels. Materials and methods At weaning, Wistar female rats were divided into two groups that were fed either a control diet (fat=7% w/w) or a high-fat diet (15% w/w). Rats were mated at 70 days (M1) and their pups (P1) were the first generation; P1 rats were mated at 70 days (M2) and their pups (P2) represented the second generation. At weaning, mothers and pups (M1, M2 and P1, P2) were measured body weight (W) and composition (% body fat, %BF), and total skeleton bone mineral content (BMC), expressed as %BMC, using chemical and DXA methods respectively. Results At weaning, high-fat diet groups M2 and P2 showed significant increases in W and %BF (p<0.05); increased %BF values were already found in the M1 and P1 groups (p<0.001). By contrast, %BMC significantly decreased in M2 and P2 rats (p<0.001).Conclusion This study demonstrates the need to review certain eating habits to avoid perpetuation of unhealthy patterns generation after generation (AU)